The Caladium steudneriifoli, a plant that pretends to be sick all day every day.

Everyone has pretended at least once in their life to be ill, to avoid school, work or going out on a rainy day. Well, today I will talk to you about the Caladium steudneriifolium, a plant that pretends to be ill every day. This plant is found in the rainforest of Colombia, Peru and Ecuador, where it regularly gets consumed and attacked by mining moth caterpillars (Soltau, Dötterl, Liede-Schumann, 2009). To avoid being eaten, the plant will produce irregular white patches on top of its leaves, called variegation, that are similar to the one left after being consumed by a caterpillar (Figure 1) (Soltau, Dötterl, Liede-Schumann, 2009). This mimicry will protect the plant, as the female moth will believe that another larvae has already consumed a part of the leaf. Therefore, the insect will assume that it does not contain enough resources for its offspring anymore, and will avoid laying its eggs on the ill looking leaves (Soltau, Dötterl & Liede-Schumann, 2009).

A research by Soltau, Dötterl & Liede-Schumann (2009) has found that leaves showing variegation patterns are 4 to 12 times less damaged than the other plain green leaves.

 So, yes…

IT WORKS!

Figure 1. Left photo: A leaf of a Caladium steudneriifolium, damaged by a
mining moth caterpillar
Right photo: A leaf of a Caladium steudneriifolium mimicking the damage
by a mining moth caterpillar.
Photo by: M. Walker.

Reference list:

Soltau, U. Dötterl, S. & Liede-Schumann, S. (2009). Leaf variegation in Caladium steudneriifolium (Araceae): a case of mimicry? Evolutionary Ecology, 23, 503-512.

Walker, M. (n.d.).Left photo: A leaf damaged by a mining moth caterpillar, Right photo: A leaf mimicking the damage by a mining moth caterpillar [Image]. Retrieved from: http://news.bbc.co.uk/earth/hi/earth_news/newsid_8108000/8108940.stm

The relationship between the Passion Flower (Passiflora) and the Zebra longwing butterfly (Heliconius chaithonia)

Figure 1. Photo of a Zebra longwing
 butterfly (Heliconius charithonia)
Photo by: C. Quigley.

The zebra longwing butterfly (Heliconius charithonia) (Figure 1) is a species of butterfly that uses the leaves of the Passion flower (Passiflora) plants to feed its larvae (figure 2) (Williams & Gilbert, 1981). To do so, the butterfly will lay its eggs directly on the leaves of the plant, and when the eggs will hatch they will simply feed on them (Williams & Gilbert, 1981). So obviously this is a great way for the butterfly to ensure the surviving of its offspring, but on the other hand the plant loses a part of its leaves each time an egg hatches. 

Figure 2. Photo of two larvae of the
 Zebra longwing butterfly (Heliconius
 charithonia), feeding on the Passion
 flower (Passiflora) leaves.
Photo by: H. Nendick-Mason.

Figure 3. Photo of the Passion Flower
(Passiflora) leaves imitating the Zebra
 long wing (Heliconius charithinia)
butterfly eggs.
Photo by: G. Dimijan & M. B. Dimijan.

This competition between the Passion flower plant and the longwing butterfly has pushed the plant to evolve and develop an effective defense mechanism. The passion flower will indeed mimic eggs on the top of its leaves so the butterfly will automatically think that the leaves have already been used by another butterfly for its young. Therefore, it will look for another available plant to make sure there will be enough available resources for its offspring (Williams & Gilbert, 1981). According to Williams & Gilbert (1981) this mimicry significantly decreases the number of eggs on the leaves and consequently reduces the herbivory by the larvae.

Reference list

Dimijan, G. & Dimijan, M. B. (n.d.).  Passion Flower (Passiflora) leaves imitating the butterfly eggs [Image]. Retrieved from: http://adarwinstudygroup.org/biology-culture-psychology/mimicry/

Nendick-Mason, H. (n.d.). Photo of 2 larvae of the Zebra longwing butterfly (Heliconius charithonia), feeding on the Passion flower (Passiflora)[Image]. Retrieved from: http://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/zebra_longwing.shtml

Quigley, C. (n.d.). Photo of a Zebra longwing butterfly (Heliconius charithonia) [Image]. Retrieved from: http://my.chicagobotanic.org/events/zebra-longwing-the-friendliest-butterfly-around/

Williams, K. S. & Gilbert, L. E. (1981). Insects as Selective Agents on Plant Vegetative Morphology: Egg Mimicry Reduces Egg Laying by Butterflies. Science, 212(4493), 467-469.